Did you found an update named as “Localization for English”, it is the build 14998. It is assumed that it was accidentally pushed by Microsoft considering that no official announcement has been made.

A warning has been issued from some users who installed it which says that this build is potentially unstable may not allow you to upgrade to upcoming builds without downgrading to Windows Phone 8.1/10 (the one which came with your phone when shipped).

Anybody installing the localization 14998 update, do not I repeat do not install it or the update system will be broken for ever on (cont)— Gustave M. (@gus33000) January 12, 2017

If you find that you are unable to download this update which means Microsoft might have pulled it back.